Production method for aluminum killed molten steel containing sulfur

Abstract

The invention discloses a production method for aluminum killed molten steel containing sulfur, and the production method mainly solves the technical problems that control over impurities in the aluminum killed molten steel containing the sulfur produced by converter smelting in the prior art is difficult, and normal casting of a slab continuous casting machine cannot be met. According to the technical scheme adopted by the invention, the production method for the aluminum killed molten steel containing the sulfur comprises the following steps of: adopting a top-bottom combined blowing converter to smelt molten steel, and adding the following raw materials of metal main ingredients including, by weight, 92%-100% of molten iron and the balance light waste steel; controlling slagging auxiliary materials in a converter smelting process, and adding the converter slagging auxiliary materials to conduct slagging while introducing oxygen to ignite by a converter oxygen lance; controlling a converter smelting end point, and detecting w[C] in molten steel at the converter smelting end point; immediately tapping after converter blowing is ended; transporting molten steel to a refining furnace for controlling the temperature of the molten steel and regulating alloy components; and transporting the molten steel to an RH furnace to refine. The aluminum killed molten steel containing the sulfur is produced by the method and is good in quality and good in pourability.

Description

technical field [0001] The invention relates to a production method of free-cutting steel, in particular to a production method of sulfur-containing aluminum killed molten steel, which belongs to the technical field of steel smelting and continuous casting. Background technique [0002] Sulfur-containing aluminum-killed steel is a kind of sulfur-based free-cutting steel. It is generally used to make parts that require high finish and size, such as: instruments, auto parts, precision instrument parts, mechanical parts, etc. The chemical composition weight percentage of sulfur-containing aluminum killed steel is generally: C 0.15% ~ 0.65%, Si 0.15% ~ 0.55%, Mn 1.00% ~ 1.70%, P≤0.040%, S0.02% ~ 0.06%, Cr 1.00% ~1.50%, Al 0.01%~0.05%, Fe balance. The role of elemental sulfur is that sulfur is distributed in the steel in the form of manganese sulfide. MnS cuts off the continuity of the matrix and makes the steel body easy to break. MnS also has a lubricating effect, thereby redu...

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Problems solved by technology

[0004] The purpose of the present invention is to provide a production method of sulfur-containing aluminum-killed molten steel, which mainly solves the difficulty in controlling inclusions in the sulfur-containing aluminum-killed molten steel produced by converter smelting in the prior art and cannot satisfy the normal casting of slab continuous casting machines. Technical problem; The sulfur-containing aluminum killed molten steel that the inventive method produces, on the one hand, by Al in steel 2 o 3 The inclusions are treated with calcium and denatured to low melting point 12CaO·7Al 2 o 3 On the other hand, the calcium treatment process will not generate CaS inclusions, which solves the control of CaS inclusions in molten steel; the method of the present invention realizes the control of sulfur-containing aluminum-killed molten steel inclusions and the normal casting operation of slab continuous casting machines

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